1. Field of the Invention
The present invention is related to an image compressing apparatus, an image compressing method, and an image compressing program. More specifically, the present invention is related to an image compressing apparatus, an image compressing method, and an image compressing program that extract regions of interest from images, and perform image compression such that the image quality of the regions of interest and other regions are different. In addition, the present invention is related to an image decompressing apparatus, an image decompressing method, and an image decompressing program that decompress compressed images.
2. Description of the Related Art
There are known techniques in which characteristic regions are extracted from within images, the images are divided into the characteristic regions and background regions other than the characteristic regions, and the characteristic regions and the background regions are compressed at different compression rates (refer to U.S. Patent Application Publication No. 20100119156, for example). The technique disclosed in U.S. Patent Application Publication No. 20100119156 extracts characteristic region images from a plurality of images that constitute a video, and generates a characteristic region video and a background region video. The characteristic region video is compressed by a compressing section for compressing the characteristic region to generate characteristic region video data, and the background region video is compressed by a compressing section for compressing the background region to generate background region video data. The characteristic region video data and the background region video data are correlated to each other by adding tag data or the like, then are output via a communications network.
The technique disclosed in U.S. Patent Application Publication No. 20100119156 employs separate compressing sections to compress the characteristic region video and the background region video. In this technique, it is necessary to provide the same number of compressing sections as the number of videos to be compressed, which results in the cost of circuits increasing corresponding to the number of compressing sections which are provided. In addition, the technique disclosed in U.S. Patent Application Publication No. 20100119156 generates the characteristic region video data and the background region video data as separate streams. Therefore, it is necessary to manage the two sets of video data such that they are correlated, in order to obtain the original video, which is troublesome.